In order to maintain the health of the animal colony, principles of animal husbandry that provide an ideal environment for the animals is essential. Consistent with federal mandated practices, the requested equipment will maximize the comfort and health of the animals, minimize moisture and ammonia levels in the cages, and provide an effective barrier from possible pathogens. The requested individual ventilated caging provides an ideal microenvironment for the animal. If this request is awarded, we can house all our mice in ventilated racks, except for mice housed in our BSL-2 suite that cannot accommodate a ventilated rack. Not only will these racks enhance the husbandry of the animals, it will also allow us to expand our housing capacity by 13%, which is essential to keep up with the growth of our animal program (currently we house approximately 18,000 mice. Expanding the number of ventilated racks will enhance our abilities to ensure the welfare of the animals, as well as, provide increased flexibility to respond to the changing needs of the investigators. As the ventilated cages house more animals than standard racks, which accommodates the growing animal usage needs of our expanding animal research program. Housing rodents in ventilated racks like Sealsafe Plus will protect them from infective agents and protect the animal users from allergens and requires a high volume of air to be blown into the cages so as to provide the optimal micro-environment, thus aiming to maintain a low concentration of ammonia, carbon dioxide and a stable concentration of oxygen.